1. Field of the Invention
The present invention relates to a voice (i.e. sound) recording and reproducing apparatus which is adapted to memorize digitally coded data formed by coding voice waveforms, and also to reproduce synthesized voice waveforms by reading and decoding the memorized coded data.
2. Description of the Prior Art
Generally, referring to FIG. 1, a memory element 1 has a plurality of data storing segments which are given with address numbers. If the bit length of each data storing segment (maximum word length) is not equal to the bit length of the coded data of the voice, the coded data is stored in the memory segment in the following manner.
As shown in FIG. 1, one word of coded data is stored in one memory segment of a memory element 1 with the right end of the stored data word being aligned at the right end of its respective memory segment. Thus, there will be a non-used space (indicated by a back-slash) in each segment. In this manner, a plurality of data areas A, B and C, each comprising a string of coded data words, are formed in the memory element 1 as shown in FIG. 2(a).
If the data in the data area B (FIG. 2(a)) of coded data of voice is erased, data area C is shifted next to data area A, thus causing a vacant area 2 which has formed in the memory element 1, to be enlarged as shown in FIG. 2(b). Accordingly, this increased vacant area in the memory element 1 is ready for use in the next recording. As is understood from FIG. 2(b), the vacant area 2 is formed by shifting coded data in the data area C towards the front end of the memory by the control of, e.g., a CPU (central processing unit). Such a data shift will be referred to as a data transfer within the memory.
In the above-described prior art arrangement, however, if the maximum word length acceptable to each memory segment in the memory element is longer than the word length of entered coded data words, the area indicated by the back-slash in FIG. 2(a) will not be used, thus, wasting the memory area.
Moreover, since the non-used memory areas are shifted without any change during the data transfer within the memory, the memory element 1 includes the non-used memory area even after the data transfer as shown in FIG. 2(b).